"""Integration tests for Supervisor hot-reload with enable/disable/enable flow.

These tests exercise the actual Supervisor._on_config_change code path,
not just AdapterState math in isolation. They verify the rate-limit
guarantee is maintained across adapter stop/start cycles.

IMPORTANT: These tests are designed to:
- FAIL on unfixed code (Test B fails because last_completed_poll is lost)
- PASS on fixed code (last_completed_poll is preserved across disable/enable)
"""

import asyncio
import base64
import os
from datetime import datetime, timedelta, timezone
from pathlib import Path
from unittest.mock import AsyncMock, MagicMock, patch

import pytest
import pytest_asyncio

from central.config_models import AdapterConfig
from central.crypto import KEY_SIZE, clear_key_cache


def adapter_is_running(state) -> bool:
    """Check if adapter is running (compatible with both fixed and unfixed code)."""
    # Fixed code has is_running property; unfixed checks task directly
    if hasattr(state, 'is_running'):
        return state.is_running
    return state.task is not None and not state.task.done()


async def cleanup_adapter(supervisor, name: str) -> None:
    """Clean up adapter (compatible with both fixed and unfixed code)."""
    # Fixed code has _remove_adapter; unfixed uses _stop_adapter which pops
    if hasattr(supervisor, '_remove_adapter'):
        await supervisor._remove_adapter(name)
    else:
        await supervisor._stop_adapter(name)

# Test database DSN
TEST_DB_DSN = os.environ.get(
    "CENTRAL_TEST_DB_DSN",
    "postgresql://central_test:testpass@localhost/central_test",
)


@pytest.fixture(scope="session")
def master_key_path(tmp_path_factory: pytest.TempPathFactory) -> Path:
    """Create a master key file for the test session."""
    key = os.urandom(KEY_SIZE)
    key_path = tmp_path_factory.mktemp("keys") / "master.key"
    key_path.write_text(base64.b64encode(key).decode())
    return key_path


@pytest.fixture(autouse=True)
def setup_master_key(master_key_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
    """Configure master key path for all tests."""
    clear_key_cache()
    monkeypatch.setenv("CENTRAL_DB_DSN", TEST_DB_DSN)
    monkeypatch.setenv("CENTRAL_MASTER_KEY_PATH", str(master_key_path))


class MockConfigSource:
    """Mock ConfigSource for testing Supervisor without DB."""

    def __init__(self) -> None:
        self._adapters: dict[str, AdapterConfig] = {}

    def set_adapter(self, config: AdapterConfig | None, name: str | None = None) -> None:
        """Set or remove an adapter config."""
        if config is None:
            if name:
                self._adapters.pop(name, None)
        else:
            self._adapters[config.name] = config

    async def list_enabled_adapters(self) -> list[AdapterConfig]:
        return [a for a in self._adapters.values() if a.enabled and not a.is_paused]

    async def get_adapter(self, name: str) -> AdapterConfig | None:
        return self._adapters.get(name)

    async def watch_for_changes(self, callback) -> None:
        # No-op for testing
        return

    async def close(self) -> None:
        pass


class MockNWSAdapter:
    """Mock NWSAdapter that tracks poll calls and allows control."""

    requires_api_key = None  # Mock adapters don't require API keys

    def __init__(self, config, config_store, cursor_db_path) -> None:
        self.config = config
        self._config_store = config_store
        self.cadence_s = config.cadence_s
        self.states = set(s.upper() for s in config.settings.get("states", []))
        self.poll_count = 0
        self.poll_times: list[datetime] = []
        self._shutdown = False

    async def startup(self) -> None:
        pass

    async def shutdown(self) -> None:
        self._shutdown = True

    async def apply_config(self, config: AdapterConfig) -> None:
        """Apply new configuration."""
        self.config = config
        self.cadence_s = config.cadence_s
        self.states = set(s.upper() for s in config.settings.get("states", []))

    async def poll(self):
        """Yield nothing - we just track that poll was called."""
        self.poll_count += 1
        self.poll_times.append(datetime.now(timezone.utc))
        return
        yield  # Make this an async generator

    def is_published(self, event_id: str) -> bool:
        return False

    def mark_published(self, event_id: str) -> None:
        pass

    def bump_last_seen(self, event_id: str) -> None:
        pass

    def sweep_old_ids(self) -> int:
        return 0


@pytest.fixture
def mock_nats():
    """Mock NATS connection."""
    mock_nc = AsyncMock()
    mock_nc.publish = AsyncMock()
    mock_js = AsyncMock()
    mock_js.publish = AsyncMock()
    mock_nc.jetstream.return_value = mock_js
    return mock_nc


@pytest.fixture
def mock_config_store():
    """Mock ConfigStore for testing Supervisor."""
    store = MagicMock()
    store.list_streams = AsyncMock(return_value=[])
    store.get_stream = AsyncMock(return_value=None)
    store.set_adapter_last_error = AsyncMock()
    store.get_api_key = AsyncMock(return_value=None)
    return store


class TestEnableDisableEnableIntegration:
    """Integration tests for enable→disable→enable flow through Supervisor.

    These tests verify that _on_config_change → _stop_adapter → _start_adapter
    preserves last_completed_poll correctly.
    """

    @pytest.mark.asyncio
    async def test_enable_disable_enable_gap_longer_than_cadence(
        self, mock_nats, mock_config_store, tmp_path: Path
    ) -> None:
        """Test A: Re-enable after gap longer than cadence polls immediately.

        - Start adapter (cadence 60s)
        - Simulate completed poll 5 minutes ago
        - Disable adapter
        - Re-enable adapter
        - Assert next poll fires immediately (last+cadence is in past)
        - Assert exactly ONE poll happens, not multiple catch-up
        """
        from central.supervisor import Supervisor, AdapterState

        config_source = MockConfigSource()
        initial_config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(initial_config)

        supervisor = Supervisor(
            config_source=config_source,
            config_store=mock_config_store,
            nats_url="nats://localhost:4222",
            cloudevents_config=None,
        )

        # Mock NATS connection
        supervisor._nc = mock_nats
        supervisor._js = mock_nats.jetstream()

        # Patch NWSAdapter to use our mock
        # Inject mock adapter into supervisor's registry
        supervisor._adapters["nws"] = MockNWSAdapter
        # Start supervisor (starts adapter)
        await supervisor._start_adapter(initial_config)

        state = supervisor._adapter_states.get("nws")
        assert state is not None
        assert adapter_is_running(state)

        # Simulate completed poll 5 minutes ago
        state.last_completed_poll = datetime.now(timezone.utc) - timedelta(minutes=5)
        saved_last_poll = state.last_completed_poll

        # Disable adapter
        disabled_config = AdapterConfig(
            name="nws",
            enabled=False,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(disabled_config)
        await supervisor._on_config_change("adapters", "nws")

        # Verify stopped but state preserved (THIS IS THE KEY CHECK)
        # On unfixed code, state will be NONE because pop() removes it
        # On fixed code, state still exists with is_running=False
        state = supervisor._adapter_states.get("nws")
        assert state is not None, (
            "State was removed on stop! This violates the rate-limit guarantee. "
            "State should be preserved to maintain last_completed_poll."
        )
        assert not adapter_is_running(state)
        assert state.last_completed_poll == saved_last_poll

        # Re-enable adapter
        reenabled_config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(reenabled_config)
        await supervisor._on_config_change("adapters", "nws")

        # Verify restarted with preserved last_completed_poll
        state = supervisor._adapter_states.get("nws")
        assert state is not None
        assert adapter_is_running(state)
        assert state.last_completed_poll == saved_last_poll

        # The loop should detect that last_poll + cadence is in the past
        # and poll immediately. Let's verify by checking the wait time logic.
        now = datetime.now(timezone.utc)
        next_poll_at = saved_last_poll.timestamp() + 60  # cadence = 60s
        wait_time = max(0, next_poll_at - now.timestamp())

        # last_poll was 5 minutes ago, cadence is 60s
        # next_poll_at = 5_minutes_ago + 60s = 4_minutes_ago
        # wait_time should be 0 (poll immediately)
        assert wait_time == 0, (
            f"Expected immediate poll (wait=0), got wait={wait_time}s. "
            f"last_poll was {saved_last_poll}, now is {now}"
        )

        # Cleanup
        supervisor._shutdown_event.set()
        await cleanup_adapter(supervisor, "nws")

    @pytest.mark.asyncio
    async def test_enable_disable_enable_gap_shorter_than_cadence(
        self, mock_nats, mock_config_store, tmp_path: Path
    ) -> None:
        """Test B: Re-enable after gap shorter than cadence respects rate limit.

        THIS IS THE KEY TEST that failed before the fix.

        - Start adapter (cadence 60s)
        - Simulate completed poll 10 seconds ago
        - Disable adapter
        - Re-enable adapter 20 seconds later (still within cadence window)
        - Assert next poll fires at last_poll + 60s, NOT immediately
        """
        from central.supervisor import Supervisor, AdapterState

        config_source = MockConfigSource()
        initial_config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(initial_config)

        supervisor = Supervisor(
            config_source=config_source,
            config_store=mock_config_store,
            nats_url="nats://localhost:4222",
            cloudevents_config=None,
        )

        supervisor._nc = mock_nats
        supervisor._js = mock_nats.jetstream()

        # Inject mock adapter into supervisor's registry
        supervisor._adapters["nws"] = MockNWSAdapter
        # Start adapter
        await supervisor._start_adapter(initial_config)

        state = supervisor._adapter_states.get("nws")
        assert state is not None

        # Simulate completed poll 10 seconds ago
        state.last_completed_poll = datetime.now(timezone.utc) - timedelta(seconds=10)
        saved_last_poll = state.last_completed_poll

        # Disable adapter
        disabled_config = AdapterConfig(
            name="nws",
            enabled=False,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(disabled_config)
        await supervisor._on_config_change("adapters", "nws")

        # Verify stopped but state preserved (THIS IS THE KEY CHECK)
        # On unfixed code, state will be NONE because pop() removes it
        # On fixed code, state still exists with is_running=False
        state = supervisor._adapter_states.get("nws")
        assert state is not None, (
            "State was removed on stop! This violates the rate-limit guarantee. "
            "State should be preserved to maintain last_completed_poll."
        )
        assert not adapter_is_running(state)
        assert state.last_completed_poll == saved_last_poll

        # Re-enable adapter (simulate 20 seconds later, but we're just
        # checking the rate limit logic)
        reenabled_config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(reenabled_config)
        await supervisor._on_config_change("adapters", "nws")

        # Verify restarted with preserved last_completed_poll
        state = supervisor._adapter_states.get("nws")
        assert state is not None
        assert adapter_is_running(state)
        assert state.last_completed_poll == saved_last_poll

        # The loop should detect that last_poll + cadence is still in the future
        # and wait until then.
        now = datetime.now(timezone.utc)
        next_poll_at = saved_last_poll.timestamp() + 60
        wait_time = max(0, next_poll_at - now.timestamp())

        # last_poll was ~10 seconds ago, cadence is 60s
        # wait_time should be ~50s (60 - 10 = 50)
        assert 45 < wait_time < 55, (
            f"Expected ~50s wait (respecting rate limit), got wait={wait_time}s. "
            f"Rate limit violated: poll would happen before last_poll + cadence"
        )

        # Cleanup
        supervisor._shutdown_event.set()
        await cleanup_adapter(supervisor, "nws")

    @pytest.mark.asyncio
    async def test_enable_disable_delete_readd_fresh_state(
        self, mock_nats, mock_config_store, tmp_path: Path
    ) -> None:
        """Test C: Delete then re-add clears preserved state.

        - Start adapter
        - Simulate completed poll
        - Disable adapter
        - DELETE adapter from DB (not just disable)
        - Re-add adapter with same name
        - Assert preserved timestamp is dropped (fresh adapter, immediate poll)
        """
        from central.supervisor import Supervisor

        config_source = MockConfigSource()
        initial_config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(initial_config)

        supervisor = Supervisor(
            config_source=config_source,
            config_store=mock_config_store,
            nats_url="nats://localhost:4222",
            cloudevents_config=None,
        )

        supervisor._nc = mock_nats
        supervisor._js = mock_nats.jetstream()

        # Inject mock adapter into supervisor's registry
        supervisor._adapters["nws"] = MockNWSAdapter
        # Start adapter
        await supervisor._start_adapter(initial_config)

        state = supervisor._adapter_states.get("nws")
        assert state is not None

        # Simulate completed poll 10 seconds ago
        state.last_completed_poll = datetime.now(timezone.utc) - timedelta(seconds=10)

        # Disable adapter
        disabled_config = AdapterConfig(
            name="nws",
            enabled=False,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(disabled_config)
        await supervisor._on_config_change("adapters", "nws")

        # DELETE adapter from DB (remove from config source)
        config_source.set_adapter(None, name="nws")
        await supervisor._on_config_change("adapters", "nws")

        # Verify adapter fully removed
        assert "nws" not in supervisor._adapter_states

        # Re-add adapter with same name
        new_config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(new_config)
        await supervisor._on_config_change("adapters", "nws")

        # Verify new adapter started fresh
        state = supervisor._adapter_states.get("nws")
        assert state is not None
        assert adapter_is_running(state)
        # last_completed_poll should be None (fresh adapter)
        assert state.last_completed_poll is None, (
            f"Expected None (fresh adapter), got {state.last_completed_poll}. "
            f"Preserved state not cleared on delete."
        )

        # Cleanup
        supervisor._shutdown_event.set()
        await cleanup_adapter(supervisor, "nws")

    @pytest.mark.asyncio
    async def test_stop_preserves_state_start_reuses_it(
        self, mock_nats, mock_config_store, tmp_path: Path
    ) -> None:
        """Verify _stop_adapter preserves state and _start_adapter reuses it."""
        from central.supervisor import Supervisor

        config_source = MockConfigSource()
        config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(config)

        supervisor = Supervisor(
            config_source=config_source,
            config_store=mock_config_store,
            nats_url="nats://localhost:4222",
            cloudevents_config=None,
        )

        supervisor._nc = mock_nats
        supervisor._js = mock_nats.jetstream()

        # Inject mock adapter into supervisor's registry
        supervisor._adapters["nws"] = MockNWSAdapter
        # Start adapter
        await supervisor._start_adapter(config)

        state = supervisor._adapter_states.get("nws")
        state.last_completed_poll = datetime.now(timezone.utc) - timedelta(seconds=30)
        saved_poll = state.last_completed_poll

        # Stop adapter
        await supervisor._stop_adapter("nws")

        # State should still exist
        assert "nws" in supervisor._adapter_states
        state = supervisor._adapter_states["nws"]
        assert not adapter_is_running(state)
        assert state.last_completed_poll == saved_poll

        # Restart adapter
        await supervisor._start_adapter(config)

        # Should reuse existing state
        state = supervisor._adapter_states.get("nws")
        assert adapter_is_running(state)
        assert state.last_completed_poll == saved_poll

        # Cleanup
        supervisor._shutdown_event.set()
        await cleanup_adapter(supervisor, "nws")

    @pytest.mark.asyncio
    async def test_remove_adapter_clears_state(
        self, mock_nats, mock_config_store, tmp_path: Path
    ) -> None:
        """Verify _remove_adapter fully clears state."""
        from central.supervisor import Supervisor

        config_source = MockConfigSource()
        config = AdapterConfig(
            name="nws",
            enabled=True,
            cadence_s=60,
            settings={"states": ["ID"], "contact_email": "test@test.com"},
            paused_at=None,
            updated_at=datetime.now(timezone.utc),
        )
        config_source.set_adapter(config)

        supervisor = Supervisor(
            config_source=config_source,
            config_store=mock_config_store,
            nats_url="nats://localhost:4222",
            cloudevents_config=None,
        )

        supervisor._nc = mock_nats
        supervisor._js = mock_nats.jetstream()

        # Inject mock adapter into supervisor's registry
        supervisor._adapters["nws"] = MockNWSAdapter
        await supervisor._start_adapter(config)

        state = supervisor._adapter_states.get("nws")
        state.last_completed_poll = datetime.now(timezone.utc)

        # Remove adapter
        await cleanup_adapter(supervisor, "nws")

        # State should be gone
        assert "nws" not in supervisor._adapter_states